/*
*Copyright (c) 2021, Alibaba Group;
*Licensed under the Apache License, Version 2.0 (the "License");
*you may not use this file except in compliance with the License.
*You may obtain a copy of the License at

*   http://www.apache.org/licenses/LICENSE-2.0

*Unless required by applicable law or agreed to in writing, software
*distributed under the License is distributed on an "AS IS" BASIS,
*WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*See the License for the specific language governing permissions and
*limitations under the License.
*/

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

/*
 * Modifications Copyright Havenask Contributors. See
 * GitHub history for details.
 */

package org.havenask.script.expression;

import org.apache.lucene.search.DoubleValuesSource;
import org.havenask.index.fielddata.IndexFieldData;

/**
 * Expressions API for geo_point fields.
 */
final class GeoField {
    // no instance
    private GeoField() {}

    // supported variables
    static final String EMPTY_VARIABLE        = "empty";
    static final String LAT_VARIABLE          = "lat";
    static final String LON_VARIABLE          = "lon";

    // supported methods
    static final String ISEMPTY_METHOD        = "isEmpty";
    static final String GETLAT_METHOD         = "getLat";
    static final String GETLON_METHOD         = "getLon";

    static DoubleValuesSource getVariable(IndexFieldData<?> fieldData, String fieldName, String variable) {
        switch (variable) {
            case EMPTY_VARIABLE:
                return new GeoEmptyValueSource(fieldData);
            case LAT_VARIABLE:
                return new GeoLatitudeValueSource(fieldData);
            case LON_VARIABLE:
                return new GeoLongitudeValueSource(fieldData);
            default:
                throw new IllegalArgumentException("Member variable [" + variable + "] does not exist for geo field [" + fieldName + "].");
        }
    }

    static DoubleValuesSource getMethod(IndexFieldData<?> fieldData, String fieldName, String method) {
        switch (method) {
            case ISEMPTY_METHOD:
                return new GeoEmptyValueSource(fieldData);
            case GETLAT_METHOD:
                return new GeoLatitudeValueSource(fieldData);
            case GETLON_METHOD:
                return new GeoLongitudeValueSource(fieldData);
            default:
                throw new IllegalArgumentException("Member method [" + method + "] does not exist for geo field [" + fieldName + "].");
        }
    }
}
